JaLCDOI 10.18926/14121
フルテキストURL Mem_Fac_Eng_OU_40_1_40.pdf
著者 三宅 隆| 東辻 千枝子| 鶴田 健二| 東辻 浩夫|
抄録 The electron system of arbitrary degeneracy can be mapped onto a classical system where electrons of the same spin are assigned an additional interaction and the effect of degeneracy is taken into account through an imaginative temperature. We apply this method to electrons in quantum dots modeled as two-dimensional electron liquid confined in a finite domain by a harmonic potential. We analyze distribution functions by molecular dynamics instead of solving integral equations which are not so useful in the case without translational invariance.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 2006-01
40巻
1号
開始ページ 40
終了ページ 43
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002308268
JaLCDOI 10.18926/15442
フルテキストURL Mem_Fac_Eng_OU_28_1_87.pdf
著者 Motojima Isao| 河野 伊一郎| 西垣 誠|
抄録 In recent years, construction or planning of large-scale underground structures, such as underground power plants, underground oil storage plants and nuclear power plants have been coming into consideration in Japan. To construct such as large-scale underground structures, one of the most important problems is to make clear beforehand the behavior of groundwater around these structures and the other is to carry out proper countermeasure of groundwater, so that these structures can be constructed safely and maintained stability over a long time period. This report describes the results of theoretical studies on the drain systems and at the same time, discusses the drain systems around the underground cavern for the practical underground power stations.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1993-11-30
28巻
1号
開始ページ 87
終了ページ 128
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307220
JaLCDOI 10.18926/46950
フルテキストURL mfe_38_1-2_033_037.pdf
著者 Liman, M. Sanusi| Totsuji, Chieko| Tsuruta, Kenji| Totsuji, Hiroo|
抄録 The dynamic structure factor and the spectrum of the momentum-density fluctuations of 2D Yukawa liquids are analyzed in the domain of weak and intermediate coupling and screenlng parameters. The dispersion relations of the longitudinal and transverse collective excitations are obtained and compared with the random phase approximation (RPA) and harmonic approximation for triangular lattice.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 2004-03
38巻
1-2号
開始ページ 33
終了ページ 37
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 80016863329
JaLCDOI 10.18926/19961
フルテキストURL Mem_Fac_Eng_OU_44_69.pdf
著者 Nekado, Kenta| Kato, Hidehiro| Nogami, Yasuyuki| Morikawa, Yoshitaka|
抄録 Recently, pairing–based cryptographies have attracted much attention. For fast pairing calculation, not only pairing algorithms but also arithmetic operations in extension field should be efficient. Especially for final exponentiation included in pairing calculation, squaring is more important than multiplication. This paper proposes an efficient squaring algorithm in extension field for Freeman curve.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 2010-01
44巻
開始ページ 69
終了ページ 72
ISSN 1349-6115
言語 English
論文のバージョン publisher
NAID 120002309070
JaLCDOI 10.18926/15428
フルテキストURL Mem_Fac_Eng_OU_29_2_83.pdf
著者 都留 寛治| Nishiyama Chikako| 大槻 主税| 尾坂 明義|
抄録 One of the CaO,SiO(2)-based bioactive glasses(5OCaO・ 5OSiO (2) in mol%) were soaked for various periods in a simulated body fluid(SBF) with or without containing alcohols such as methanol, ethanol, and 1-propanol. Effect of the alcohols was investigated on the apatite formation on the glass surface with thin-film X-ray diffraction, FT-IR reflection spectroscopy and scanning electron microscopy. Under the presence of alcohols up to 0.1mol/l in the SBF an apatite layer was formed on the glass, while it consisted of crystallites similar in morphology but larger in size than that found for the SBF without the alcohols. It was concluded that the alcohols little influenced the the apatite forming ability of the CaO,SiO(2)-based glasses.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1995-03-27
29巻
2号
開始ページ 83
終了ページ 88
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307301
JaLCDOI 10.18926/47021
フルテキストURL mfe_36_2_001_006.pdf
著者 Sakakibara, Akira| Kanadani, Teruto| Tashiro, Tsutomu| Yoshioka, Kazumi|
抄録 The effect of heat-treatment conditions on occurrence of serration in Al-Zn alloys was investigated. Specimens were aged for various times up to 2.6Ms at 293K or 273K after quenching from various temperatures (T(Q)), 473K to 853K, and tensile-tested at room temperature. Serration occurred more easily according as T(Q) became lower and the aging time became shorter: in the case that T(Q)=473K serration was observed even after aging for 2.6Ms, while in the case that T(Q)=773K serration did not occur irrespective of aging conditions. Serration was also recognized when the specimens were furnace-cooled from 773K to room temperature. These results together with those obtained by the electrical resistometry suggest that the serration in the low'concentrated Al-Zn alloy is caused by the formation of small GP zones whose Guinier radius is less than 1nm or some sort of solute clusters.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 2002-03
36巻
2号
開始ページ 1
終了ページ 6
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 80015497758
JaLCDOI 10.18926/15484
フルテキストURL Mem_Fac_Eng_OU_25_1_15.pdf
著者 榊原 精| Kanadani, Teruto|
抄録 Aging of Al-lmass % Ag alloy at 273K after quenching under various conditions was studied by measurement of electrical resistivity. Scattering of the quasi-equilibrium value of resistivity (p(e)) was not random but closely related to the as-quenched value (p(o)); P(e) increased with increasing p(o)' When the quenching temperature (T(q)) was lower than or equal to 773K, the state at p(e) was controlled substantially by the concentration of quenched vacancy. On the other hand, when T(q)>823K, GP zones formed during quenching played an important role, instead of quenched vacancies, in determining the state.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1990-12-14
25巻
1号
開始ページ 15
終了ページ 21
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307255
JaLCDOI 10.18926/19604
フルテキストURL Mem_Fac_Eng_OU_33_1_1.pdf
著者 榊原 精| Kanadani, Teruto|
抄録 Aging of diolute Al-Ag alloys after quenching from low temperatures were studied mainly by electrical resistometry. Maximum resistivity observed in the aging curve of specimens quenched from high temeperature disappeared when the quenching temperature was lowered to 473 or 453K. When the quenching temperature was lowered further to 423K or lower, however, maximum resistivity reappeared. At the temperature lower than or equal to 423K but higher than the GP zone solvus, the alloys were not homogeneous but had clusters of solute atoms or fluctuation of solute concentration. Inhomogeneous distribution of solute atoms may affect the aging behavior after quenching from that temperature.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1998-11-30
33巻
1号
開始ページ 1
終了ページ 4
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002309092
JaLCDOI 10.18926/15356
フルテキストURL Mem_Fac_Eng_OU_34_13.pdf
著者 榊原 精| Tanimoto, Tadashi| Matsushima, Takahisa| Hosokawa, Norio| Kanadani, Teruto|
抄録 Repeated tensile fatigue strength of the low temperature age-hardened Al-Zn alloys is investigated varying the specimen thickness. Fatigue strength of the age-hardened specimens decreases with the specimen thickness when the specimen is thinner than a certain thickness, whereas fatigue strength of non age-hardened specimens, i.e., pure aluminum and dilute Al-Zn alloy, does not depend the specimen thickness. The dependence of fatigue strength on the thickness of age-hardened specimen is considered to be caused by the decrease of the strength of specimen as a whole, as a result of increase in volume ratio of the soft surface layer formed after age-hardening with decreasing specimen thickness.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 2000-03-27
34巻
1-2号
開始ページ 13
終了ページ 17
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307815
JaLCDOI 10.18926/15407
フルテキストURL Mem_Fac_Eng_OU_26_1_1.pdf
著者 榊原 精| Kanadani, Teruto|
抄録 Reversion of the age-hardened Al-15mass % Zn alloy, in which ellipsoidal GP zones were formed, was investigated by hardness test. Ellipsoidal zones were reverted more quickly near the surface and grain boundary than in the interior, as spherical zones did. The results confirm their role as sources for vacancies in reversion.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1991-11-30
26巻
1号
開始ページ 1
終了ページ 7
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002308003
JaLCDOI 10.18926/15387
フルテキストURL Mem_Fac_Eng_OU_30_2_9.pdf
著者 榊原 精| Kanadani, Teruto|
抄録 Fatigue strength of Al-Cu alloy was examined by a repeated tensile mode when the specimens were aged and reversion annealed. The specimen quenched from 723K and aged fully around room temperature showed fatigue strength which depended on the existence of soft layer, while the specimen quenched from 723K and aged in the same way showed fatigue strength independent of the existence of the soft layer. Fatigue strength of the specimen, of which the soft surface layer was removed, was the same for either quenching temperature. Fatigue strength became higher when the soft surface layer was thickened with reversion annealing for 600s at 323K after aging. The soft surface layer was thought to increase fatigue strength of the aged Al-Cu alloy as well as Al-Zn alloy.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1996-03-29
30巻
2号
開始ページ 9
終了ページ 13
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307694
JaLCDOI 10.18926/15466
フルテキストURL Mem_Fac_Eng_OU_24_1_1.pdf
著者 吉田 彰| 大上 祐司| 藤井 正浩|
抄録 To clarify the effects of a drive system lubricant additive upon rolling fatigue of rollers manufactured from carburized and hardened steel, three types of oil were used as lubricants: one mineral base oil and the other two mineral base oils to which an S-P additive package and ATF additive package were added, respectively. These specimens were tested for sliding/rolling fatigue and examined for failure on the surface, rolling fatigue strength, and other properties. Roller surface temperatures and inter-roller frictional coefficients were found scarcely affected by the type of oil used. Irrespective of the difference in oil type, failure on the surface was found to be entirely spalling attributable to cracks generated in the subsurface. The depth at which spalling cracks had taken place was found nearly coincident with the depth at which a ratio of reversing orthogonal shear stress to hardness had amplitude A(Tyz/Hv) maximized. These depths were larger as Hertz stress became more prominent. Nevertheless, they were found hardly affected by the type of oil. Although rolling fatigue strength did not show a significant difference dependent upon the type of oil, it may be said that fatigue life would be somewhat negatively affected by an extreme pressure coated film with a content of sulfur and phosphorus.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1989-11-29
24巻
1号
開始ページ 1
終了ページ 12
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307588
JaLCDOI 10.18926/19962
フルテキストURL Mem_Fac_Eng_OU_44_73.pdf
著者 Imanaka, Hiroyuki| Tanaka, Soukichi| Feng, Bin| Imamura, Koreyoshi| Nakanishi, Kazuhiro|
抄録 We used modified Czapek-Dox (mCD) or dextrin-peptone-yeast extract (DPY) media to cultivate a filamentous fungus, Aspergillus oryzae IAM 2706 by three different cultivation methods, i.e., shaking-flask culture (SFC), agar-plate culture (APC), and membrane-surface liquid culture (MSLC), to identify the differences in cultivation behaviors and gene transcriptional profiles. The fungi cultivated by APC or MSLC secreted a greater number of different proteins/enzymes in larger quantities compared with fungi cultivated by SFC, particularly when DPY medium was used. In particular, the amounts of protease secreted by fungi cultivated via MSLC or APC were much greater compared with SFC. When mCD medium was used, α-amylase activity was barely detectable in all cultures while the activity was detected in MSLC and APC in a quantity that was several times higher than that in SFC using DPY medium. SDS-PAGE analysis and N-terminal amino acid sequences confirmed 6 proteins in the culture supernatants when DPY medium was used. Among these proteins oryzin (an alkaline protease) and α-amylase were detected at much higher levels in APC and MSLC compared with SFC, which was consistent with the measured activity of the secreted enzymes. However, when mCD medium was used, only oryzin was detected in significant amounts in MSLC and APC. Microarray analyses of the fungi cultivated by SFC, APC or MSLC using either mCD or DPY media indicated that the gene transcriptional profile of the MSLC sample was similar to that of the APC sample but different from that of the SFC sample. When mCD medium was used, most of the genes that were up-regulated 10-folds or greater in the MSLC sample relative to the SFC sample were unknown or predicted proteins. Transcription of the oryzin gene was only slightly up-regulated in the MSLC sample while transcription of the α-amylase gene was slightly down-regulated. On the other hand, when DPY medium was used, many known genes including the oryzin gene were up-regulated in the MSLC sample versus the SFC sample.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 2010-01
44巻
開始ページ 73
終了ページ 83
ISSN 1349-6115
言語 English
論文のバージョン publisher
NAID 120002309053
JaLCDOI 10.18926/14150
フルテキストURL Mem_Fac_Eng_39_1_46.pdf
著者 門野 恵典| 東辻 千枝子| 鶴田 健二| 東辻 浩夫|
抄録 We present a real-space, polynomial-expansion approach to electron dynamics in nanostructured semiconductors. The Chebyshev expansion method is employed for efficient calculation of timeevolution of single-electron wave function. Details of the formulation are described. The method is applied to the electron transport in nanostructured semiconductors such as Si nanowires. The mean-square displacement and diffusivity of electron in Si chains are obtained as functions of length of the chains. The results show clearly ballistic behavior of electron in the pure Si chain.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 2005-01
39巻
1号
開始ページ 46
終了ページ 51
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002308231
JaLCDOI 10.18926/15395
フルテキストURL Mem_Fac_Eng_OU_27_1_65.pdf
著者 奈良 重俊| Hara Yuji| 東辻 浩夫|
抄録 Quantum mechnical electron wave transfer between two quantum wires which are weakly coupled via a thin potential barrier is considered. The total electronic states are calculated with both analytical ( no field case ) and numerical methods ( under applied electric fields ). The transfer efficiency is evaluated for several specified cases of geometrical structures, potential barrier heights and the externally applied electric field. Estimated trasfer time is of the order of one picosecond in typical mesoscopic structures. The model in this paper can be used to determine important structure parameters for experiments on electron directional coupler controled by external elctric field.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1992-11-25
27巻
1号
開始ページ 65
終了ページ 79
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307405
JaLCDOI 10.18926/20011
フルテキストURL Mem_Fac_Eng_OU_29_1_7.pdf
著者 Hiroyuki Tachibana| 東辻 浩夫| 奈良 重俊| 東辻 千枝子|
抄録 Effects of interface fluctuations on the electronic states in semiconductor quantum dots are analyzed on the basis of numerical solutions for ground state wave functions and energy eigenvalues. It is shown that the effective volume of confinement becomes smaller than the real volume of quantum dots due to fluctuation. This effect comes from the fact that the wave functions with larger characteristic wavelength are not able to deform themselves following the fluctuation of interfaces exactly.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1994-11-30
29巻
1号
開始ページ 7
終了ページ 14
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002310741
JaLCDOI 10.18926/15383
フルテキストURL Mem_Fac_Eng_OU_30_1_89.pdf
著者 東辻 千枝子| Sanaka Yoshiaki| 東辻 浩夫|
抄録 Based on the tight-binding method, electronic bands of the mixed perovskite oxides are calculated in order to develop the electronic theory of ferroelectric phase transitions in these mixtures which are difficult to describe within the phenomenological theories. Diagonal elements of Hamiltonian matrix of parent materials are assumed to differ by 0.1eV and mixtures are simulated by lattices of supercells containing 2(3) = 8 or 3(3) = 27 unit cells randomly assigned to either material. The width of the conduction and valence bands have maxima and the band gap has a minimum at intermediate mixing ratio. Results are in agreement with those of other analyses on random systems and even 2(3)-cell computation seems to serve as a first approximation for our purpose.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1995-12-28
30巻
1号
開始ページ 89
終了ページ 97
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307957
JaLCDOI 10.18926/15359
フルテキストURL Mem_Fac_Eng_OU_34_19.pdf
著者 Okada, Akira| Uno, Yoshiyuki| Okajima, Isao|
抄録 In EDM, the machining characteristics greatly depend on the energy distribution. Therefore, it is very important to clarify the energy distribution for understanding various phenomena in EDM. In this paper, the energy distribution in EDM with graphite electrode is investigated by measuring the temperatures of electrode and workpiece. Experimental analysis shows that the material removal rate depends on energy density while the electrode wear greatly depends on the adhesion of heat resolved carbon from machining fluid, and the energies distributed into electrode and workpiece are almost constant regardless of pulse duration.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 2000-03-27
34巻
1-2号
開始ページ 19
終了ページ 26
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307707
JaLCDOI 10.18926/15415
フルテキストURL Mem_Fac_Eng_OU_29_2_29.pdf
著者 岡 久雄| 福田 敬|
抄録 In the stiffness evaluation from the skin surface, the body structure under the skin, like a bone and muscle, influences on the measurement results. The authors developed the measurement system of biomechanical impedance with applying a vibration of acoustic frequency onto the body surface. We measured the viscoelasticity of the silicone-gel model, which involves metal blocks, from the gel surface by using this system. The internal structure of model is estimated from the relation between the viscoelasticity and the distance from the gel surface to the internal block. Applying this method, the shape of ribs of the right chest are estimated. The shapes and viscoelasticity of silicone-gel tumor model, which has two different tumors, are also estimated.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 1995-03-27
29巻
2号
開始ページ 29
終了ページ 37
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 120002307199
JaLCDOI 10.18926/46979
フルテキストURL mfe_37_2_045_060.pdf
著者 Xu, Wei| Zhao, Y.| Horikane, T.| Hayata, T.| Tosuji, H.| Kagawa, Y.|
抄録 Resistivity distribution sounding of the non-homogeneous earth is important for electrical ground system design, geophysical prospecting and survey or monitoring the groundwater flow level. The previous paper presented that the direct inversion of the electric resistivity distribution in a domain is possible from the impedance data measured over the domain boundary using the dual reciprocity boundary element modelling in two-dimentional field [1]. The proposed inversion technique is extended to the distribution in three-dimensional space [2]. This technique is capable of inversion without iteration and meshing of the domain. Electric field with spatially varying conductivity is governed by Laplace equation, which is transformed into a Poisson-type expression with an inhomogeneous term involving the conductivity difference as a source term. Dual reciprocity method (DRM) is a technique for transforming the domain integral associated with the inhomogeneous term in Poisson equation into the boundary integral expression. The resistivity distribution in the field can thus be identified from the data observed over its boundary, for which some examples are demonstrated [2]. In this paper, the examination is extended to the case where only the data measured over the single surface is used for the inversion.
出版物タイトル Memoirs of the Faculty of Engineering, Okayama University
発行日 2003-03
37巻
2号
開始ページ 45
終了ページ 60
ISSN 0475-0071
言語 English
論文のバージョン publisher
NAID 80016037881